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My 13-year-old cat has persistent diarrhea. What should I do?

Updated On September 23rd, 2025

Pet's info: Cat | American Shorthair | Male | neutered

Hi! My 13 yr old cat had liver enzymes that were 901 a few weeks ago but it is now normal. The vent explained to keep giving him the Denamarin until we were out even though he is normal again. He has been having trouble with diahrrea for a few weeks, but our vet found no signs of any cause. However, put him on Albon. He is now off of Albon. I have been giving him FortiFlora as well. He hasn't been able to have his flea treatment due diarrhea. This issue with diarrhea continues. Is it normal?

2 Answers

Most Helpful Answer

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Answered By Dr. Heidi DVM, CVA, CCRT, CVTP, CVSMT, CVCH

Veterinarian, Certified Veterinary Acupuncturist, Certified Canine Rehabilitation Practitioner

Published on March 30th, 2018

I'm so sorry that Shady is having problems with diarrhea. No, diarrhea is never normal, so we should continue to look for a cause and figure out how to resolve it. You did not mention if the diarrhea started before the Denamarin or after. While we like to continue Denamarin even after the liver enzymes are normal, I would certainly discuss that with your veterinarian if the diarrhea started after the Dermarin was started. If the diarrhea started before you added the Denamarin, then I would discuss with your veterinarian other options for diagnostics (such as sending a fecal sample to the lab) and treatment (such as anti-diarrheal medications). Good luck! I hope that was helpful and that Shady feels better soon. Thanks for using Petco Pet Education Center, formerly Petcoach.

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    Answered By Kevin Sanada, DVM

    Veterinarian

    Published on October 25th, 2017

    The Denamarin would not cause diarrhea. I suspect that this is related to the gastrointestinal disease that was causing the vomiting before. It doesn't appear to be a serious cause based on the recent tests, but seems like the cause (could be an infection, or parasite) of the problems is not controlled well. I recommend taking Stripes back to your vet for a recheck. Watery diarrhea is concerning, because he could get dehydrated if not treated soon enough, so it would be best to have him seen within the next day if possible. I hope that helps and Stripes gets better soon.

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